出血発作をくり返しextravasationのみられた特発性脳内血腫の1例

RECURRENT SPONTANEOUS INTRACEREBRAL HEMATOMA WITH ANGIOGRAPHIC EXTRAVASATION OF CONTRAST MEDIUM: CASE REPORT

はじめに

　脳内血腫の原因としては高血圧症，頭部外傷，脳動脈瘤あるいは脳動静脈奇型の破裂などが主なものである。近年，出血の誘因ならびに原因を明らかにしえない脳内出血を"特発性脳内血腫"と呼称し，その原因の一つとしてsmall vascular malformation^{5）6）8）10）}が注目されている。

　今回われわれは，特発性脳内血腫と考えられ，第1回手術後も昏睡状態が遷延し，初回発作約5カ月後に別の部位に新たな出血を起こし死亡した1例を経験し，第2回発作時の脳血管撮影でいわゆるextravasationと考えられる像を示したのでここに報告し，あわせて文献的考察を加えたい。

A 46-year-old female was found unconscious in bed with vomiting. She had right hemiplegia and showed urinary incontinence. Bloody CSF had been found by the referring physician.

At 4 days later admission, the principal neuro-logical findings included smicoma, right pyramidal signs and slight nuchal rigidity. There was no choked disc or anisocoria, and the pupils reacted to light sluggishly. The right corneal reflex was decreased.

The CSF was pinky and its pressure was 75mm of H₂O. Carotid angiography, electroencephalo-graphy and somatosensory evoked potentials re-vealed the presence of a space-occupying lesion in the left frontoparietal region, and its origin was showed to be small venous malformation.

By the left fronto-parietotemporal craniotomy; subarachnoidal bleeding was found in the premotor area and frontoparietal intracerebral subcortical hematoma was evacuated, but the hematoma had not encapsulated. Total volume of the hematomawas about 60g. In the anterior superficial wall of the hematoma there was a small knot of blood vessels, but the findings of angiomatous malforma-tion was not observed histologically.

Her postoperative unconsciousness continued, but the level of consciousness became gradually up hill. On 5 months after first operation, she was suddenly vomited and became comatose with pale face. The left carotid angiography revealed a space occupying lesion in the posterior portion of the infra-sylvian region and angiographic extravasation of contrastmedium.

Reopening of the previous wound disclosed sub-cortically a new intracerebral hematoma in the temporal lobe and clot of about 60g in total volume was evacuated. Histological examinations showed no findings of any vascular malformation. She died 5 days after rebleeding without autopsy.

The etiology of spontaneous intracerebral hema-toma and the findings of angiography and soma-tosensory evoked potentials were discussed.